Children's Hospital of Oklahoma at the University of Oklahoma is a member institution of the Pediatric Oncology Group. Under the direction of O.U. faculty members, patients are seen in Oklahoma City (CHO) and Tulsa (Saint Francis Hospital). Thus, the majority of pediatric patients with cancer in the state of Oklahoma are participants in a cooperative cancer program. Patient resources and scientific expertise are present in the institutions to study the natural history of childhood cancer, develop effective therapeutic regimens, and evaluate the toxicity and effectiveness of new anti-cancer agents in the treatment of childhood cancer. The program is also characterized by a number of non-therapeutic protocols, i.e., evaluation of leukemic therapy on the central nervous system of newly diagnosed leukemic patients and evaluation of consent forms. The team at the University of Oklahoma is multidisciplinary and includes pediatric hematologists/oncologists, radiation therapists, radiologists, pediatric surgeons, immunologists, and pathologists. All protocols are reviewed by the Institutional Review Board prior to activation and informed consent is obtained on all patients entered into protocols of the Pediatric Oncology Group. Protocol compliance has remained a high priority. Our one year compliance is 92% and the long-term compliance is 96% which is above the group average. The University of Mexico is affiliated with the University of Oklahoma. It serves an economically disadvantaged population and especially a minority group (native American Indians) which needs to be included in the population studied by a cooperative cancer group. The pathology department at New Mexico has special expertise in molecular diagnostic hematopathology and in solid tumors which can benefit the research effort of the Pediatric Oncology Group.